Raucous demonstrations erupted for a second night in the U.S. in protest of recent grand jury decisions rejecting charges against white police officers who killed unarmed black men.
In the western city of Berkeley, California, the protest began peacefully Sunday night at the University of California, but grew violent and spilled into nearby Oakland.
Police said they fired tear gas at hundreds of protesters after some threw rocks and bottles at them, while others set trash cans on fire, smashed store windows and looted businesses.
Other, more peaceful demonstrations were staged in several major U.S. cities.
In Chicago, hundreds of demonstrators walked out of churches and into the streets to protest what they consider the unfair and sometimes deadly treatment of black men by white police officers. Protesters in Miami blocked a portion of a highway, slowing traffic to the international art show, Art Basel, in Miami Beach, while other demonstrations occurred in New York, Philadelphia and Seattle.
President Barack Obama told an interviewer with Black Entertainment TV that racism in the United States is deep-rooted and won't soon be eliminated.
"When you are dealing with something as deeply rooted as racism or bias in any society, you've got to have vigilance, but you have to recognize that it's going to take some time and you just have to be steady," Obama said.
The latest demonstrations started Wednesday, when a New York grand jury failed to indict police officer Daniel Pantaleo for the July chokehold death of Eric Garner, a 43-year-old father of six.
In a video of Garner's arrest, he can be heard gasping, "I can't breathe," as police held him on the ground.
That decision was announced nine days after a Ferguson, Missouri grand jury chose not to indict Darren Wilson for the shooting death in August of 18-year-old Michael Brown.
New York Police Commissioner Bill Bratton said Sunday an internal investigation into Garner's death could take up to four months.
The U.S. Justice Department is also conducting an investigation to determine if Garner's civil rights were violated.
In a televised interview on Sunday, New York City Mayor Bill de Blasio said there has to be "an honest conversation" about the history of racism in the U.S. to help bring together police and the community.
Civil rights activist Al Sharpton has announced plans for a demonstration in Washington Saturday called the National March Against Police Violence to protest the killings of Garner, Brown and others.
The U.N. special rapporteur on minority issues, Rita Izsak, has called for a review of policing in the United States.
Izsak said the two grand jury decisions "leave many with legitimate concerns relating to a pattern of impunity when the victims of excessive use of force come from African-American or other minority communities."
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